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volts writes "According to New Scientist no one was able to grab the two $50,000 top prizes in the recent NASA 'Beam Power Challenge'. The biggest limiting factor seemed to be that no team was able to meet the speed requirement, although a group from the University of Saskatchewan in Canada set the height record at 12 meters. Not quite geosynchronous..."

The biggest limiting factor seemed to be that NASA didn't offer enough money to get any remotely reasonable solution to the problem. Fifty thousand dollars is chump change to the kind of money needed to develop any of this technology.

I was about to say the same thing... on the other hand, they're doubling it for next year. Hopefully they will continue to increase it substantially ever year until there is a winner (or it just isn't worth it anymore).

Starting out low and moving up seems like a good way to ensure you get the best price if you're not in a great hurry. (Isn't that what a Dutch auction is?).

The biggest limiting factor seemed to be that NASA didn't offer enough money to get any remotely reasonable solution to the problem. Fifty thousand dollars is chump change to the kind of money needed to develop any of this technology.

These challenges typically cost more to compete in than you can win. DARPA autonomous vehicles teams typically spent 2-3 times the prize. The X-prize was won by a team spending $26 million on a $10 million prize.

What you "win" is prestige and advancing the state of the art.

Also, at least one elevator climber team was only 3 people part-time. That's not a huge budget...

Actually what you "win" is licenseable technology that costs you $10 million less to develope and open the door to the posibility of getting the real "prize" which happens to be much larger (Also know as venture capital).

Getting venture capital is not "winning". It is a very expensive form of financing, in terms of dilution, and should be exercised as a last resort. The effective interest rate of venture capital (if it were to be compared to a loan), in terms of the return expected by VC, is around 20-25%.

$50K for a design and prototype isn't a lot, but since student labor is basically free most of the money can go towards building the prototype. The biggest problem seems to be that the energy source available seems to be the light energy from a couple hundred watt lamp. Assuming that the bulb is 50% efficient that doesn't leave a lot of energy to move even the motors at the required speed, let alone the entire vehicle.

Short of a superconductor, practical wired power transmission is measured in hundreds or at best thousands of miles. Tens of thousands would be too much to hope for.

Are you sure? Quoting the article I linked:

"On the fundamental side, a perfect metallic nanotube should be a ballistic conductor: in other words, every electron injected into the nanotube at one end should come out the other end. Although a ballistic conductor does have some resistance, this resistance is independent of its length, which means that Ohm's law does not apply. Indeed, only a superconductor (which has no electrical resistance whatsoever) is a better conductor."

With a resistance of 6500 ohms per tube independent of length and current densities of 10^7 amperes per square cm practical 10,000 mile power cables become a matter of long enough tubes (no, the tubes do not have to be 10,000 miles long).

"$50K for a design and prototype isn't a lot, but since student labor is basically free most of the money can go towards building the prototype."

As a research professor with students who could have tried to build this thing, take my word for it that it's not enough money. I refuse to have my students doing someone else's research for free; I want to be able to pay them at least $10/hour + tuition remission. For an undergraduate at my fairly inexpensive institution, that's about $7K per quarter, and I'd need three of these. Add a $20K equipment budget and $5K for my time and we are at $46K.

So the budget is $50K. What's the problem? Just the obvious one that my chance of winning is quite difficult to estimate, but certainly way less than 100%. I'd put my expected return at around $5K. There may be institutions and individuals who can afford to expect to lose $41K for the prestige of doing good research and the prospect of future funding. I'm not one, so I'm out.

It doesn't appear that I am unique in these calculations.

By contrast, I just finished a NASA Phase I SBIR. $68,000 over 6 months, guaranteed. If I wanted to do space elevator research, I'd be way better off submitting an SBIR proposal than entering the contest: small up-front risk, higher expected return, better prospects of future funding.

Contests are run because there are often folks who overvalue them, so they are sometimes a cheap way to get things done at the expense of others.

As a research student, I would have been interested in working on a project like this as an extra-curricular activity, if the materials had been provided. Being on the winning team would look very good on anyone's CV, being on a losing team would have been good experience, and probably quite fun as well. I suspect I am not alone in believing this - and that would shave $21K off your budget requirements at the start. That gives a $25K investment for a potential $50K (plus marketing capital) return - not f

It's great for research students to work for free on projects. I just want them to be my projects, not someone else's. See my PSAS [pdx.edu] and SDR [pdx.edu] stuff for examples of where I've successfully deployed students to learn, have fun, gain experience, and pad their CVs. See my Summer of Code [pdx.edu] site for an example of where they've actually gotten paid to do it.

Sadly, changing the prize from $50K to $100K doesn't change the economics much. In my previous post I was estimating (perhaps wildly wrongly) that this year's

For an undergraduate at my fairly inexpensive institution, that's about $7K per quarter, and I'd need three of these. Add a $20K equipment budget and $5K for my time and we are at $46K.

Considering that equivalent in industry care and feeding for 3 full-time engineers would be over $500k ($55k ea + a $100k manager + $100k janitorial/HR/security staff + $100k equipment + office space,) 3 students for $46k is free. However, private companies are in this for the publicity that brings venture capital, not the ch

The point of the exercise is not to win $50,000. The idea is to give people an idea of what particular technologies NASA is looking to invest in.NASA and other government agencies regularly offer research grants to develop the technology they want. This is just a way to do the same thing on the cheap. Rather than offering several different parties hundred thousand dollar research grants, you offer a prize to the winner of a contest, and hype up the contest. That way, people get fame as well as the possi

I'm reminded of DARPA Grand Challenge 1. This, though, seems quite a bit easier than autonomous vehicles- perhaps not the tether, but the climbers seem straighforeward. Are solar panels really that heavy? Are they that inefficient? The article says there was only a six-month time period between the contest announcement and the contest, but there isn't much in the way of new technology needed here. What gives?

Are solar panels really that heavy? Are they that inefficient? The article says there was only a six-month time period between the contest announcement and the contest, but there isn't much in the way of new technology needed here.

I think maybe they are going about this the wrong way... Most people are thinking heavier than air object lifts. What they really should need is a hellium ballon that can make the lift from 0-50km and where lighter than air (or lighter than the atmosphere around it) no longer beco

Go back to steam engines, stirling engines? If your power source is light, why bother with electrical engines? Use some liquid gas as fuel in a tank, use the projected light as a heat source, let the gas heat up in a combustion chamber (a piston?) and drive the whole thing up as a locomotive:)

Stirling Engine. Definately. That way, you don't have to carry extra 'fuel'.I can see this working. A stirling engine, with the 'heating' chamber on the outside. Target it with a laser (not allowed this year, but will be next), and you'll have a very efficent climber.

You do need to track the machine with the laser (it might help to shoot straight up), and dissipating the heat would be a problem for a 'real' application (heat doesn't dissipate as easy in a vacum), but that wouldn't be a problem for the h

You still have a few hundred thousand feet of climbing in non-zero vacuum, and much, much farther than that in significant gravity, for a proper space elevator. Why not use these environments to advantage (eg. balloons and counter-weights, just off the top of my head)? It's the same idea behind a space plane - you'll likely need different engines for different stages of the journey, each one optimized to a particular operating regime. I'm sure the ideal climber in the low-atmosphere, low-G environment at

One of the big points about the space elevator scenario is that descending cars can generate electricity. Ideally, you would want to use this to help power the ascending cars to minimize wasted energy. If you're feeding ascending cars electricity anyway, you may as well convert all incoming energy into that form.

I say use the best tool for the job. If the best tool for lifting an elevator up is a steam engine or a Stirling engine then use that. But it doesn't mean electricity should not be used at all. There can be 2 engines on an elevator that goes that high up. Even if only for redundancy.

I didn't think of that as the really hard part in the space elevator problem. I'm sure somebody will figure out how to build a climber. I would have thought that the hard part is figuring out how to build a cable that the climber could climb, which seems to involve scaling up the best known materials by 10 orders of magnitude.

It reminds me of the old joke about the drunk looking under the lamppost for the quarter he dropped in the alley, because that's where the light is better.

I think its a matter of "first things first." The climber currently is the most attainable technologocal component. The cable will require breakthroughs in new materials to be viable, and I doubt a contest for $50,000 is going to speed that up.

... was disqualified for "inappropriate" elevator music... Under testing situations, all of our patients (read: monkeys, elderly, humans, and fish) were driven insane, then promptly driven sane, then insane, then sane, and so forth during the 62.5 mile elevator ride finished. After the tenth go around we decided the cost to hosing out the compartment filled with bile, blood, and bits of hair were not worth the cash prize. So it goes.
Additionally, the PSP battery life wasn't sufficient to stave off elevator-maddness either.
http://trs.nis.nasa.gov/archive/00000377/01/tm1085 37.pdf [nasa.gov]

Why would I try to win this year when the prize money doubles for next year?
"Next year, both contests will be repeated but the top prizes will rise to $100,000."
Let me guess... the year after that the prize money goes to $250k?
Sounds backward to me...

I don't think it's backwards at all. If someone wins, there won't be *any* money next year. The prize money could increase until it's enough to get it done. Competition ensures that it doesn't just keep rising.

In fact, I'd say this sounds like a better approach than "submit your proposal and we'll give you a pile of money" for things that are experimental and preliminary like this.

The top prize is 50K...deduct 50% for university overhead, about 12K for graduate student salary, 5K for professor salary, and you might have 8K for materials budget. What happens when you need a special diode that costs 2K?

It sounds like a great idea, they should sweeten the pot a little more (and I did RTFA, 100K won't be enough either).

Jules Verne thought that in the future man would get to the moon by being fired there in a bullet shaped craft from a gigantic canon, and for a time afterwards many scientists agreed that the easiest way to get something into orbit would be some form of "Verne canon". Of course then you get all those wacky guys in the 20s playing around with rockets with good results. Later some Germans sped up the research into these rockets to be used as weapons of war and the development of rocket systems well, skyrocketed. Several of their best rocket scientists went to the West after WWII and development continued, though this time the focus was split between missile design and space exploration. Meanwhile, in Canada a few nutty guys were involed in a little project called the High Altitude Research Program [astronautix.com] (HARP), the idea was that payloads could simply be fired into orbit by a huge canon, mind you the payloads would be inorganic (satellites, radar chaff, other innert material, etc) because the escape velocity would be too great for living creatures to widthstand.

At the time (the 60s) people were interested in sending people into space, not to mention the Canadian Gov't no longer had interest in the project it was killed off by 1967. Now, I think the focus has changed a bit (what with successful robotic expeditions and the desire for a cheap way to get material into orbit) that the Verne Canon might once again be relevant.

Escape velocity isn't the problem. It's the massive acceleration from the cannon.
A cannon accelerates a projectile from a standing start to massive speed in a very short amount of time. This means a massive acceleration for a small period of time - and so a massive force on your payload. Some simple calculations:
Say the cannon takes 0.5 secs to fire. Escape velocity is 11100m/s.
Your payload would be feeling an acceleration of 22200m/s^2 = 2220 Gs.
Humans die at less than 20G. Your sensitive electronic

> Escape velocity isn't the problem. It's the massive acceleration> from the cannon.A cannon cannot accelerate a projectile to a velocity higher than the speed of sound in the hot gases generated by the propellant. It is not practical to get the gases hot enough to push the speed of sound in them to escape velocity.

> Your sensitive electronics will be mush at well below 1000G's, or> below 100G's if they have moving parts.

The military have been putting clockwork mechanisms in artillery shells fo

What I don't understand is why they don't just supply power on the cables that they are climbing. I realize that in a real elevator, the cables would be carbon fiber or something else that isn't conductive material. Is it too much to run a metal wire for power? Does it add that much weight? If so, this is a serious limitation to the whole space elevator idea. It is going to take a lot of energy to take more than a token amount of cargo into orbit... even on an elevator.Here I thought that the elevator itsel

In a real space elevator, you would have a metal wire running all the way past geosynch. orbit - of a thick enough guage to power something that is hauling a large satellite. Yeah, that would add too much mass. There isn't too much in the way of needing to figure out how to power it.Basically, the thought process is this:Don't bring fuel - it's a waste of effort hauling it up.Don't get energy from the elevator - too much mass.So, energy has to be beamed to the crawler.

Given that length of cable, wouldn't there be some electric current running through it anyway?There was that experiment where the space shuttle released a long length of cable, which consequently melted and snapped due to the electric currents from the local magnetic field/solar wind.

> I realize that in a real elevator, the cables would be carbon fiber> or something else that isn't conductive material.Actually, carbon fibers can be remarkable conductors. They can be "ballistic conductors" with the interesting characteristics of resistance independent of length and current densities of 10^7 amps per sq cm.

If ballistic conductivity is confirmed and turns out to be compatible with the needed strength and the fibers can be made long enough supplying power along the cable may be quite

A lunar space elevator isn't as simple as you might think. Given the moon's proximity to the Earth, the only stable place to deploy one is from the midpoint of the far side. Given the moon's slow rate of rotation, it's more difficult to keep the tether up. You'd need one pretty much as long as those proposed for an Earth-based space elevator.

That's why its a challenge. If the parameters are too easy you don't get great innovation.

If I could change anything I would have allowed the competitors to design, build and provide their own energy source instead of using the NASA provided light. That would have allowed another track of innovation.

He adds that teams were restricted to using NASA's searchlight as the power source this year, but says they will be able to design their own in 2006. "They can use lasers, microwaves, whatever they like," he says.

The minimum speed was 1 meter/s = 3.6km/h = 2.2369 miles/h. I can walk faster than that.
Geosynch is 35,786 km above sealeve according to wiki. At 3.6 km/h it would take over a year to get up to geosynch. They really should increase the minimum speed.

There were a number of factors arguing for slower speed initial prize goals.

Power source this time was limited to a single high-power searchlight... faster requires a whole lot more power, and it simply wasn't going to be available in time.

Most teams didn't have the chance to test at their own facility with their own searchlight, nor at the competition site. If you can't really test, you shouldn't assume highly efficient operations...

The tether in use wasn't that tall, and accellerating and decellerating a whole lot within the available vertical distance was a nonstarter.

This was a introduction to parts of the problem set, not a realistic attempt to engineer production grade tether climbers. Everyone involved knows that...

Excellent point! In fact, most Space Elevator proponents seem to miss the fact that the energy for the elevator isn't free. You still have to expend at least the minimum amount of energy required to move an object into LEO. The physics of the situation say there are no shortcuts.

What you DO gain is:

a) Slower ascentb) Only minor (if not inconseqential) losses from air frictionc) Ability to expend the power over a long period of time vs. in a huge controlled explosiond) A workable descent mode that doesn't require that the hull handle extremes

I'm all for the space elevator idea. However, a lot of people need to understand that this is NOT existing technology. While it's very much possible for the necessary breakthroughs to be completed in the next few decades, dropping everything and working on a Space Elevator would only mean that we'd lose space access for a very long time. That is why NASA is pursuing the CEV and not the Space Elevator as the next major launch vehicle.

e) 'Unlimited' energy that can be created on location or fed from an existing grid, instead of shipping around limited quantities of hazardous chemicals. You'll need to choose between cheap and fast, though.

You've missed a major point to the space elevator scenario--controlled descent.

In a standard descent, all the excess kinetic energy is wasted as heat. In a space-elevator scenario, you can use the energy of the descending cars to assist in powering the ascending cars. Net overall energy expenditure required is just enough to start the system and overcome the inevitable inefficiencies. Your average energy-per-car can be much lower than the rocket scenario.

Sometimes those inefficiencies add up to many times more than the theoretically required work. For example, you only need some tiny fraction of a gallon of gas to accelerate a car to 70mph. If there was no rolling friction and no air resistance, you could probably get 1000mpg out of your car on a typical highway (you would only use fuel when accelerating and climbing hills). Reality is not so kind.Based on that, I would expect that in a space elevator system, the descending car would only be able to prov

Actually, there are cars out there with 5000+ mpg at an average speed of 20mpg. Of course, they don't meet safety standards.

Remember, for much of it's travel distance the car is in very thin atmosphere, if not vacuum. Air resistance will not be a factor under those conditions. Wire losses will, unless they also develop a superconducting wire to transmit power along the cable.

There will certainly be frictional losses, but I think your estimate is pretty pessimistic.

And yet Edwards, who designed probably the most calculated-out elevator, doesn't call for this.Why? Elevators would have to pass each other. You'd have to have multiple running at a single time, transferring energy. You can't transfer over the length of the cable, so they could only transfer when close - which means a *lot* of cars going up and down. Plus, at least early-on, up traffic is much more in demand of the cable's stress than.

I always thought having the energy stored on the ground was a good idea, and just giving the rocket an initial kick to avoid the first stage.I remember reading about the amount of energy used to get a large rocket moving from 0 to x mph. If the first stage could be provided on the ground in the form of a gun or a mag-lev push, it would shave tons off the system and be reusable. Problem is, the cargo may have to take a lot of G forces, so it may only be good for dead weight cargo.

Well, yes, but you're borrowing much of that energy from the momentum of the cable, and you're replacing most of it when you ride the cable back down. You lose due to entropy, of course, but it's orders of magnitude more efficient than a rocket boost up and a free fall down.

The advantages you point out are also real, but they're minor compared to the energy efficiency of it.

Actually, you still need to expend the energy to "climb" the cable up to orbital velocity. However, as I mentioned in another post you get almost as much energy back by generating power on the way down, and you can feed that power to the climbing cars.

Each individual car requires energy to be input to ascend, and feeds energy back on the descent. If you have cars going in matched pairs (one up, one down), then the overall energy consumption of the cable could be relatively low.

You missed the most important gain to be had from a climber with a ground-based energy source. Guess what most of the fuel in a rocket is used for. That's right, most fuel is used to haul up the fuel used to haul up the fuel used to boost the rocket up to escape velocity. With a space elevator, all fuel goes towards lifting the actual payload and climber (minus atmospheric losses).

Actually, that's not true. with a space elevator, the overwhelming majority of the energy is wasted as loss. High coherency lasers with acceptable atmospheric frequencies have less than 1% wallplug to energy output efficiency; microwaves are far worse. Then there's the atmospheric losses, losses in the adaptive optics, and losses on the solar cells (not as bad as one might expect since the cells are optimized for a single frequency, but still not great).The benefit in the case of the space elevator is th

Actually, I think we may be over-complicating it. Trains run on rails and pick their power up from another rail. If you can streach one cable to g-sync orbit, you can streach several. If the cable and orbital-station can 'stay-up' when stuff gors up or down the cable, why not have permenant stations?Until some effective "power-beam", or practically-sized self-contained power source (maybe fusion one day) is developed, you can power capsules using good-old power-rail systems, with repeater generation station

If you can streach one cable to g-sync orbit, you can streach several.

That's only if the carbon nanotube is sufficiently conductive. Regular copper wire or the like wouldn't have sufficient strength to span the distance. Also, it's quite possible that your line losses on such a cable would be nearly as bad as a cohesive energy beam.

And, if I am grokking this correctly, this line would be the temperature of geo-stationary orbit, or at least damn cold, and therefore super-conductors would be effective in slas

Geosynch is 35,786 km above sealeve according to wiki. At 3.6 km/h it would take over a year to get up to geosynchTrue, but as gravity decreases, you accelerate faster per unit energy. I can't be arsed to actually do any math, but 1m/s at 1G is going to translate into significantly higher velocity the further out you go. Besides which, if you want to use the elevator primarily for moving materiel rather than personnel, a one-year turnaround might not be too bad; throughput is potentially more important than lag.

Even for personnel, that's on the order of time it took to sail from Europe to America via wind power, and people did that.

Even for personnel, that's on the order of time it took to sail from Europe to America via wind power, and people did that

http://www.bartleby.com/65/co/ColumbusC.html [bartleby.com]
On Aug. 3, 1492, Columbus sailed from Palos, Spain, with three small ships, the Santa María, commanded by Columbus himself, the Pinta under Martín Pinzón, and the Niña under Vicente Yáñez Pinzón. After halting at the Canary Islands, he sailed due west from Sept. 6 until Oct. 7, when he changed his course

Totally unnecessary. If the capsule goes up at 1m/s, it will run 1km in 1000 seconds and 200km in 200,000 seconds, which is about 55.5 hours. At that distance the speed of the capsule can be raised by other means.

I think it has more of a chance of working than you. How's the view from the family basement, junior?
The thing that people fail to realize is that even if a project never reaches its goal, it has the potential to spawn innovation that can be applied to other problems. There is a quite a list of things that are NASA castoffs that are used in everyday life.

That is a myth [snopes.com]. The space program was responsible for a lot more [nasa.gov] than Tang and 'space pens'. Then again, there are things that you can't put a price on, such as the need for mankind to go to space.

Wow, I've never heard anyone claim that any of those, apart from Tang, were by-products of the space program.Sounds to me like someone build a straw-man. Note that others have posted links to actual products that resulted from the space program.

Teflon: Teflon was invented by DuPont in 1938, well before the space program existed. NASA makes no claim to ever inventing teflon and anyone who tells you other wise is an idiot. What they do claim to have spun off is a material that contains teflon. Two completely differnt concepts.

I am quite annoyed that NASA would even risk $50,000 of mine and other tax payer's money on such a preposterous game.

But this is what government is for. In a republic such as ours, the presumption is that a service or commodity for which any dolt can see the need is going to be supplied by the private market. Why not? You can get rich doing so (cf. Gates, Bill). On the other hand, there are a few things that people as individuals or even large firms can't provide (such as national security) or won't provide because it isn't obvious they're going to work -- such as space elevators.

Enter the government. It's government's job to finance "preposterous flights of fancy," because private industry (very sensibly) won't. Most of that blue-sky stuff turns out to be nonsense, naturally, But some of it doesn't. Some of it, in fact, turns out to be ideas so ingenious that they seemed like pure folly to ordinary folks -- that would be you and me and nearly all other voters -- when they were originally proposed. And, of course, these are the clever ideas that will sustain our ability, a hundred years from now, to compete internationally on the basis of being smarter than anyone else, not working for less. I don't know about you, but I prefer to work in a high-wage, low-volume economy than a low-wage, high-volume economy.

Now, there's no doubt a proper amount of bread that government should cast on the waters. We could argue about that. But not in this case. I don't see how anyone who accepts the role of government in financing very basic research could figure that $50,000 out of a $1.8 trillion Federal Budget is wildly over the top.

Mmm, but let us think this all the way through. If there is no more international competition, then there is no more difference between nations. That means we all live under one political system.However....my absolute preferred top-notch hurray huzzah political system is, I dare say, not quite the same as yours. Or as other/. denizens. And perhaps even very different from what a Wyoming rancher or Bill Gates or Robert Mugabe likes. Which brings up an interesting question: which political system is the